Various types of parametric amplifiers constructed as semiconductor devices with successions of zones of semiconductor material are known in the prior art. For example, U.S. Pat. No. 2,884,607 describes a semiconductor non-linear capacitance diode in which a single crystal semiconductor body is composed of regions of alternate p and n-type conductivity with the impurity concentration which in each zone is arranged so that the concentration gradient adjacent to successive junctions is alternately gradual and abrupt. The device is able to function as a parametric amplifier and also permits a high cutoff frequency as a result of the extremely close spacing of the junctions within the diode.
Similar structures are also found in U.S. Pat. Nos. 2,980,810, 3,938,172 and 3,982,270.
An alternative configuration of devices formed of successive layers of semiconductor material and intermediate insulating layers are found in U.S. Pat. Nos. 3,356,866, and 3,822,533.